INFO: task syz-executor.3:31661 blocked for more than 143 seconds. Not tainted 5.12.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:28016 pid:31661 ppid: 8450 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:4339 [inline] __schedule+0x916/0x23e0 kernel/sched/core.c:5147 schedule+0xcf/0x270 kernel/sched/core.c:5226 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1407 unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1949 raw_release+0x58/0x8a0 net/can/raw.c:354 __sock_release+0xcd/0x280 net/socket.c:599 sock_close+0x18/0x20 net/socket.c:1258 __fput+0x288/0x920 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:174 [inline] exit_to_user_mode_prepare+0x272/0x280 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:57 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4193eb RSP: 002b:00007ffd0b483840 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000006 RCX: 00000000004193eb RDX: 0000000000000000 RSI: ffffffff8916393e RDI: 0000000000000005 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000001b2bd2bb74 R10: 0000000000001754 R11: 0000000000000293 R12: 000000000056cb00 R13: 000000000056cb00 R14: 000000000056bf80 R15: 00000000000af90f Showing all locks held in the system: 4 locks held by kworker/u4:2/80: #0: ffff8881400fb138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881400fb138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8881400fb138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8881400fb138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8881400fb138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8881400fb138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x871/0x1600 kernel/workqueue.c:2246 #1: ffffc9000106fda8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1600 kernel/workqueue.c:2250 #2: ffffffff8d691950 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb10 net/core/net_namespace.c:557 #3: ffff8880b9c35658 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1334 [inline] #3: ffff8880b9c35658 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x21c/0x23e0 kernel/sched/core.c:5061 2 locks held by kworker/u4:7/291: 1 lock held by khungtaskd/1644: #0: ffffffff8bf79760 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6333 1 lock held by in:imklog/8132: #0: ffff888020075270 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:974 2 locks held by syz-executor.3/31661: #0: ffff88806ef3c210 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:774 [inline] #0: ffff88806ef3c210 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:598 #1: ffffffff8d691950 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1949 1 lock held by syz-executor.2/31790: #0: ffffffff8d691950 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2fa/0x760 net/core/net_namespace.c:470 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1644 Comm: khungtaskd Not tainted 5.12.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd48/0xfb0 kernel/hung_task.c:294 kthread+0x3b1/0x4a0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4849 Comm: systemd-journal Not tainted 5.12.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:task_irq_context kernel/locking/lockdep.c:4410 [inline] RIP: 0010:__lock_acquire+0x314/0x5230 kernel/locking/lockdep.c:4840 Code: 89 74 24 40 48 89 45 18 65 8b 05 9f e8 a7 7e 85 c0 0f 95 c0 48 c1 e9 03 83 e6 07 0f b6 0c 11 48 89 f2 0f b6 c0 83 c2 03 01 c0 <38> ca 7c 08 84 c9 0f 85 71 12 00 00 41 83 bc 24 dc 09 00 00 01 48 RSP: 0018:ffffc900015cfcc8 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff88802cd55eb8 RCX: 0000000000000000 RDX: 0000000000000007 RSI: 0000000000000004 RDI: ffff88802cd55ec8 RBP: ffff88802cd55eb8 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88802cd554c0 R13: 0000000000000000 R14: ffff88802cd55b78 R15: 0000000000000000 FS: 00007f6ca83538c0(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6ca589d018 CR3: 00000000163d8000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire kernel/locking/lockdep.c:5512 [inline] lock_acquire+0x1ab/0x740 kernel/locking/lockdep.c:5477 do_write_seqcount_begin_nested include/linux/seqlock.h:520 [inline] do_write_seqcount_begin include/linux/seqlock.h:545 [inline] vtime_user_enter+0x9f/0x170 kernel/sched/cputime.c:709 __context_tracking_enter+0xef/0x100 kernel/context_tracking.c:82 user_enter_irqoff include/linux/context_tracking.h:41 [inline] __exit_to_user_mode kernel/entry/common.c:129 [inline] syscall_exit_to_user_mode+0x4e/0x60 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:57 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f6ca75ebf17 Code: ff ff ff 48 8b 4d a0 0f b7 51 fe 48 8b 4d a8 66 89 54 08 fe e9 1a ff ff ff 66 2e 0f 1f 84 00 00 00 00 00 b8 27 00 00 00 0f 05 0f 1f 84 00 00 00 00 00 b8 6e 00 00 00 0f 05 c3 0f 1f 84 00 00 RSP: 002b:00007ffc195fce78 EFLAGS: 00000202 ORIG_RAX: 0000000000000027 RAX: 00000000000012f1 RBX: 00005599301e21e0 RCX: 00007f6ca75ebf17 RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 00005599301e21e0 RBP: 00007ffc195fcf70 R08: 0000000060ae9244 R09: 00007ffc197f6080 R10: 00007ffc197f6080 R11: 0000000000000202 R12: 00000000000012f1 R13: 00007ffc195fd008 R14: ffffffffffffffff R15: 0005c33fbf5d8898